XML 37 R24.htm IDEA: XBRL DOCUMENT
v3.21.2

Earnings (Loss) Per Share (Tables) | 6 Months Ended
--- | ---
Jun. 30, 2021
Earnings Per Share [Abstract] |
Basic and diluted earnings (loss) per share and securities excluded from the calculation of diluted EPS | The following table shows the basic and diluted earnings (loss) per share:
| For the three months ended June 30
| 2021 |  | 2020
| Net Income (Loss) |  | Shares (in millions) |  | Per Share |  | Net Income (Loss) |  | Shares (in millions) |  | Per Share
Net income (loss) | $ | (35.1) |  |  |  |  |  |  | $ | (26.9) |  |  |  |  |
Amount allocated to common stockholders | 100.0 | % |  |  |  |  |  | 100.0 | % |  |  |  |
Basic and diluted EPS(1) | $ | (35.1) |  |  | 90.1 |  |  | $ | (0.39) |  |  | $ | (26.9) |  |  | 89.5 |  |  | $ | (0.30) |
| For the six months ended June 30
| 2021 |  | 2020
| Net Income (Loss) |  | Shares (in millions) |  | Per Share |  | Net Income (Loss) |  | Shares (in millions) |  | Per Share
Net income (loss) | $ | (175.1) |  |  |  |  |  |  | $ | (29.6) |  |  |  |  |
Amount allocated to common stockholders | 100.0 | % |  |  |  |  |  | 100.0 | % |  |  |  |
Basic and diluted EPS(1) | $ | (175.1) |  |  | 90.1 |  |  | $ | (1.94) |  |  | $ | (29.6) |  |  | 89.4 |  |  | $ | (0.33) |
| Three months ended June 30, |  | Six months ended June 30, |  |
Securities excluded from the calculation of diluted EPS (in millions)(1): | 2021 |  | 2020 |  | 2021 |  | 2020 |  |  |  |
Share-based compensation | 2.4 |  |  | 0.6 |  |  | 2.4 |  |  | 0.7 |  |  |  |  |
Convertible preferred shares | 6.3 |  |  | 6.6 |  |  | 6.3 |  |  | 6.7 |  |  |  |  |
Convertible senior notes | 4.8 |  |  | — |  |  | 4.8 |  |  | — |  |  |  |  |
(1) In periods when we report a net loss, all share-based compensation awards, convertible preferred shares and convertible senior notes are excluded from the calculation of diluted weighted average shares outstanding because of their anti-dilutive effect on earnings (loss) per share.

X
- Definition Schedule of Earnings Per Share, Basic and Diluted and Antidilutive Securities Excluded from Computation + References No definition available. + Details
Name: | cenx_ScheduleOfEarningsPerShareBasicAndDilutedAndAntidilutiveSecuritiesExcludedFromComputationTableTextBlock
Namespace Prefix: | cenx_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_EarningsPerShareAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration